A support assembly for movable shaft in particular for machinery for the food industry

ABSTRACT

A supporting assembly including a bearing, a bearing housing having an annular element housing and a base for fixing, and a cover for close fluid tight an opening of the housing element; the cover being cup-shaped and including an annular coupling portion to a radially outer lateral surface for housing the annular element. The coupling portion provided radially on the inside with at least a pair of teeth projecting radially towards the inside of the lid; the lateral surface of the annular element housing provided with an annular seat for the teeth of the lid, including: an annular groove disposed axially spaced with respect to a front edge of the housing element; axial grooves equal to the number of teeth present and that radially interrupt the front edge; and a bottom wall provided with a plurality of alternating troughs and projections arranged offset circumferentially with respect to the axial grooves.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a support assembly for furniture trees, for example rotating, in particular intended to be mounted on machines for the food industry.

KNOWN ART

As it is known, the machines used in the food industry have many moving parts supported by sliding or rotating shafts, think for example conveyor belts, kneading machines, machines for washing of fresh food.

All these machines must be cleaned frequently, usually with water added with detergent and or disinfectants, in order to monitor the possible occurrence of bacterial colonies which may pollute foods. In particular, it is necessary that these machines do not exhibit interstices or other parts where dirt, or even only the washing water, can penetrate and stagnate. The stagnation of liquids or moisture favors in fact a possible proliferation of bacteria.

This problem is particularly felt with respect to the complex support of mobile trees, which may be either type of terminal, where is housed a terminal end of the shaft, or feed through type. These support complexes, are formed by a housing element, generally annular, provided with a base or mounting flange to the machine, by a bearing, typically a rolling bearing (but could also be a sliding bearing), mounted to ‘interior of the housing and which is coupled with the movable shaft, and a cover, normally cup-shaped, which is coupled in a forced manner on the element housing and that, in the case of through-trees, is equipped with a central through hole fitted with a seal for the shaft to pass through.

Currently we are using two different types of forced assembly: in a first type, the cover is planted, for example, snap, inside a seat formed frontally in the element housing. In the second type, instead, the cover is planted, for example, snap, externally to the element housing, for example to engage a seat formed on a radially outer lateral surface of the housing element.

In the first case it creates an annular gap all around the cover. In the second case, since the cover must also be removed to allow frequent inspection, it is necessary to provide at least one groove for the insertion of a tool (eg a screwdriver) by which to lever against the cover to remove. Moreover, it can remain even in this case, however, a gap between the lid and outer surface of the housing, due to the type of mechanical coupling used. The creation of these interstices between the housing and the cover element, the interstices in which water and dirt can stagnate, however, is entirely undesirable and does not allow to obtain valid certifications for the food industry.

Finally, the assembly of the kind described have the further drawback of being able to cause, as a result of repeated assembly and disassembly, damage to the cover and/or the creation of games, that loosen the coupling (so much so that in some cases the cover may accidentally come off) and/or that aggravate the formation of interstices where water, moisture and dirt can stagnate.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a support assembly for furniture trees, in particular intended to be mounted on machines for the food industry, without any of the drawbacks of the known art and in particular in which it ensures at the same time the absence of interstices where they can nestle water, moisture and/or dirt, and a high ease of assembly and disassembly without the use of tools and the absence of risks of damage or loosening of the coupling cover/housing element as a result of frequent disassembly.

According to the invention, there is provided a support assembly for furniture trees having the characteristics set out in the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting example of embodiment thereof, wherein:

FIG. 1 shows a front elevational view of a non-limiting embodiment of a support assembly for shafts according to the invention;

FIG. 2 shows the same view as FIG. 1, but with an element (cover) removed;

FIG. 3 shows a front elevational view of the element (cover) removed in FIG. 2;

FIGS. 4 and 5 show sectional views according to a plane indicated by IV-IV and V-V, respectively, the element of FIG. 3;

FIG. 6 illustrates in enlarged scale a detail of FIG. 5;

FIGS. 7 and 8 illustrate the same perspective view of the front three-quarters of a housing element of the support assembly according to the invention realized according to two different embodiments, FIG. 7 being relative to the embodiment of FIGS. 1 and 2 and FIG. 8 being relative to a different possible embodiment which differs from that of FIGS. 1 and 2 only for the element shown in the same FIG. 8;

FIG. 9 on an enlarged scale shows a front view in elevation and partially in section of a portion of a same detail of the housing elements illustrated in FIGS. 7 and 8; is

FIG. 10 illustrates a further enlarged scale a detail of FIG. 9.

DETAILED DESCRIPTION

With reference to FIGS. 1 to 7, number 1 indicates as a whole a support assembly for movable shafts, rotating or sliding, not illustrated for simplicity.

The support assembly 1 comprises a bearing 2 (FIG. 2), for example a rolling bearing, known and only shown schematically in broken lines for simplicity, adapted to receive in a movable shaft known manner, for example rotating, to support it, and a of the bearing housing 3 having a through seat 4 within which is received the bearing 2 in a stable and known manner, therefore not illustrated for simplicity.

The support assembly 1 is in particular intended to be mounted on machines for the food industry. For this purpose, the bearing housing 3, which is illustrated in perspective view in FIG. 7, is of the type intended to be rigidly mounted on a machine frame of a known type, not illustrated for simplicity, in particular for the food industry.

The bearing housing 3 comprises a housing element 7, in the annular complex, designed so as to be adapted to receive in a known manner, to its interior, in particular in the seat 4, the bearing 2, and a base or flange 8 of fastening to the machine frame quoted; the seat 4 in general presents an axis of symmetry that is also the axis of symmetry of the element housing 7.

Obviously, the form of realization of the bearing housing illustrated in FIGS. 1, 2 and 7 is only one of the possible; for example, the base or flange 8, which is square in the illustrated example, can take on other symmetrical or asymmetrical shapes, or be formed and offset to the side relative to the housing 7, or again, with reference to FIG. 8, where there is shown a housing of the bearing 3 b variant 3 and where the similar or identical details to those of the bearing housing 3 of FIG. 7 are indicated for simplicity with the same reference numbers, the flange 8 of the bearing housing 3 is replaced by a base 8 b that extends on both sides of the housing element 7 and 8 c by a support, substantially cylindrical, which extends radially projecting from the element of the housing 7.

In any case, the support assembly 1 always also comprises a cover 10 to close fluid tight an opening 11 of the inner housing 4 of the housing element 7 of the bearing housing 3 or 3 b, by which the seat 4 is mounted bearing 2.

The lid 10 for the bearing housing 3 or 3 b is generally cup-shaped and comprises (FIGS. 3-6) a bottom wall 12, an annular side wall 13 which extends transversely to the bottom wall 12 and a coupling portion 14 toward the bearing housing 3 or 3 b.

The coupling portion 14 is annular, is formed integrally in one piece on one end 15 of the side wall 13 opposite to the bottom wall 12 and is designed to be coupled in use with the bearing housing 3 or 3 b laterally outside the housing bearing 3,3 b, in the present case it is shaped as a cup joint and is coupled laterally and radially on the outside on a lateral surface 16 radially outside of the annular housing 7, always present in any form of realization of the housing the bearing 3 (or 3 b).

The side surface 16 and the coupling portion 14 are defined by a solid of revolution and have a common axis of symmetry coincident, in the illustrated examples, with an axis of symmetry A (FIGS. 4 and 5) of the lid 10 and which is also the ‘of the housing 7 of the symmetry axis (FIG. 8) and the seat 4.

According to a first feature of the invention, the cover 10 is made of a single piece of synthetic plastic material selected appropriately and the coupling portion 14 is provided on the side opposite to the bottom wall 12 of an annular sealing lip 18, which is It extends frontally projecting from a front edge 19 (FIGS. 4-6) of the coupling portion 14 and which is made of the same synthetic plastic material of the lid 10 so as to be elastically deformable in the radial direction from the inside towards the outside.

According to a further aspect of the invention, the coupling portion 14 of the cover 10 is provided radially on the inside of at least a pair of teeth 20 protruding radially towards the inside of the lid 10 and spaced circumferentially between them, which each extend for a limited circumferential portion of the coupling portion; in the example illustrated non-limiting teeth 20 are four, spaced by 90°.

According to another aspect of the invention, and in combination with the presence of the teeth 20 on the lid 10, the radially outer lateral surface 16 of housing annular element 7 is provided with an annular seat 21 for receiving the teeth 20 of the cover 10.

The annular seat 21 (FIGS. 7-10) consists, according to the invention, in an annular groove 22 arranged axially spaced with respect to a front edge 23 of the housing 7 delimiting the mouthpiece 11 and served by a number of axial grooves 24 equal to the number of the teeth 20 on the cover 10, which grooves 24 radially interrupt at least part of the front edge 23 of the housing element 7; and in a bottom wall 25 of the annular groove 22 which is provided with a circumferentially alternating plurality of hollows 26 and projections 27 arranged offset circumferentially with respect to the axial grooves 24. Further axial grooves 24 b (FIGS. 8 and 9) may be present for the ‘insertion of mounting tools.

The annular sealing lip 18 mates in fluidtight manner and with radial interference with a portion 28 of the radially outer lateral surface 16 of housing annular element 7, as only schematically shown out of scale and in broken lines in FIG. 6. The portion 28 it is disposed on the side opposite to the front edge 23 with respect to the annular groove 22 and consists of a portion of a conical surface having taper facing towards the cover 10.

Here and hereinafter, the term “taper” of a conical or frusto-conical surface means the side toward which the vertex of the geometric cone facing bounding this surface. Then the housing 7 annular element tapers in correspondence with the conical surface portion 26 so as to progressively decrease its radial thickness toward the lid 10.

The section of the conical surface 26 defining the tract of the radially outer lateral surface 16 of housing annular element 7 which is coupled with interference with the annular lip 18 has, according to a further aspect of the invention, an inclination with respect to its axis of a symmetry equal to an acute angle and preferably less than 10°. Furthermore, the cover 10 and the annular sealing lip 18 are made of a polymeric material, preferably but not necessarily polyurethane, by molding in a single piece.

The axial grooves 24 have a radial depth identical to the radial depth of the annular groove 22 at the axial grooves 24, so that respective bottom walls of the axial grooves and the bottom wall 25 of the radial groove 22 are arranged flush with each other.

The projections 27 of the bottom wall 25 of the annular groove 22 (FIGS. 9 and 10) each comprise a first portion 29 of circumferential raised flat surface with respect to the bottom wall 25 of the annular groove 22 and a pair of second portions of the circumferential flat surface 30 that flank the first segment 29 and forming two inclined planes that connect the first surface section 29 with the bottom wall 25 of the annular groove 22.

As already said, in the illustrated preferred embodiment, the cover 10 has two pairs of teeth 20 spaced circumferentially arranged in a symmetrical manner, staggered by 90°; in this case, the radially outer lateral surface 16 of the housing element 7 has two pairs of axial grooves 24 arranged circumferentially spaced in a symmetrical manner, displaced by 90°; and the bottom wall 25 of the annular groove 22 has a plurality of circumferential sectors having the same angular width and consisting of eight depressions 26, four of which are delimited axially by the edge 23 and the other four free as arranged in correspondence of the grooves 24, and eight projections 27; the depressions 26 are delimited by curved surfaces disposed substantially flush with the bottom wall 25 of the annular groove 22, while the projections 27 project radially with respect to the bottom wall 25 of the annular groove 22 and the depressions 26 are arranged alternating.

According to a further aspect of the invention, the cover 10 (FIGS. 3 and 6) is provided radially on the outside of a plurality of circumferential depressions 31 are arranged mutually circumferentially spaced in a regular manner, which are shaped so as to realize respective elements of gripping (for example designed to receive, each, a user's finger) adapted to allow a user to manually rotate the cover 10 with respect to the housing 7.

The circumferential depressions 31 are formed radially on the outside on the coupling portion 14 and are made so as to radially thin the coupling portion 14 in correspondence of the depressions 31 same; according to an aspect of the invention, the teeth 20 of the cover 10 are then formed radially on the inside of the coupling portion 14, each in a respective circumferential depression 31.

The depressions 31 in fact, weaken the cover 10 so as to make the coupling portion 14 is elastically deformable radially outwardly at least in correspondence of the teeth 20. In order to have an optimal combination of stiffness and flexibility of the cover 10, finally, the teeth 20 are formed substantially at the front edge 19 (FIG. 6).

Thanks to the geometry described, the coupling between lid 10 and housing element 7 presents no gap that can become a receptacle for moisture and/or dirt and is self-draining. In addition, the lip 18 also thanks to a suitable choice of the plastic material with which it is made in the cover 10, carries out an optimum hydraulic seal, preventing the entry of infiltration in the seat 4.

Finally, the innovative mechanical coupling between cover 10 and housing element 7 allows you to remove and replace the cover 10 indefinitely without damaging it, by simply turning the cover 10 either clockwise or anti-clockwise and then slide the teeth 20 along the grooves 24, by means of a typical bayonet coupling. On the contrary that in pairs bayonet of the traditions; type, however, in the coupling according to the invention, thanks to the projections 27 and the depressions 26, the cover 10, once installed, is also blocked circumferentially and therefore prevent accidental disassembly.

In fact, the insertion, after bringing the teeth 20 within the groove 22 for sliding within the slots 24, it makes a rotation of the lid 10; rotation brings the teeth 20 to engage the oblique surface 30 of the projection 27 immediately adjacent to it in the direction of rotation; the tooth 20 is therefore pushed up, continuing the rotation, progressively towards the portion of flat surface 29, movement allowed by the elasticity of the lid 10 in correspondence of the teeth 20, the product obtained by means of thinning by the depressions 31 and thanks to a suitable choice of material polymer, preferably but not necessarily polyurethane, which is made by molding the cover 10. This movement also causes a certain resistance to rotation which can be detected by the user. Continuing the rotation in the same direction, the tooth 20 descends along the other portion of the inclined surface 30 opposite the previous one and “falls” into a depression 26, which is delimited between two adjacent projections 27. The tooth 20 is therefore locked in snap against rotation.

To remove the cover 10 must simply rotate the cover 10 still the same, in the same direction or in the opposite direction, to engage the tooth one of the two projections 27 adjacent to it, after which the 20 tooth is to be in another depression 26, which is, however, arranged in correspondence with a groove 24, it is therefore possible in this position to remove the lid from the element 10 of housing 7 simply making it translate axially.

All the objects of the invention are thus achieved. 

1. A bearing assembly for movable, rolling or sliding shafts, comprising: a bearing adapted to receive the movable shaft, a bearing housing having an annular housing element and a fixing base or flange (8), and a cover for fluid-tightly closing an inlet opening of an inner seat of the housing element within which the bearing is mounted; the cover providing a bottom wall, an annular lateral wall that extends transversely to the bottom wall and an annular coupling portion towards a radially outer lateral surface of the annular housing element, the coupling portion being integrally obtained on one end of the lateral wall of the cover, opposite to the bottom wall; wherein, in combination: the cover is made in one piece of a synthetic plastic material and has the coupling portion thereof radially provided on the inside of at least one pair of teeth, radially projecting towards the inside of the cover and circumferentially spaced apart from each other, which extend each over a limited circumferential stretch of the coupling portion; the radially outer lateral surface of the annular housing element is provided with an annular seat for receiving the teeth of the cover, the annular seat including: an annular groove arranged so as to be axially spaced apart with respect to a frontal rim of the housing element delimiting the inlet opening; a number of axial grooves equal to the number of teeth present on the cover and which radially interrupt at least part of the frontal rim (23) of the housing element; and a bottom wall of the annular groove which is circumferentially provided with an alternating plurality of depressions and projecting parts, the projection parts being arranged so as to be circumferentially staggered with respect to the axial grooves.
 2. The bearing assembly according to claim 1, wherein the coupling portion is provided on the side opposite to the bottom wall of the cover with an annular sealing lip which frontally extends so as to protrude from the frontal rim of the coupling portion and which is made of the same synthetic plastic material as the cover so as to be elastically deformable in radial direction from the inside outwards; the annular sealing lip being coupled in a fluid-tight manner and with radial interference to a stretch of the radially outer lateral surface of the annular housing element arranged on the opposite side of the frontal rim with respect to the annular groove and providing a conical surface stretch having its taper facing the cover.
 3. The bearing assembly according to claim 2, wherein the conical surface stretch defining the stretch of the radially outer lateral surface of the annular housing element which is coupled with interference to the annular lip has an inclination with respect to a symmetry axis thereof forming an acute angle and preferably less than 10°.
 4. The bearing assembly according to one of the claim 2, wherein the cover and the annular sealing lip are made of polyurethane, by single-piece molding.
 5. The bearing assembly according to claim 1, wherein the axial grooves have a radial depth identical to that of the annular groove obtained on the radially outer lateral surface of the housing element at the axial grooves themselves, so that respective bottom walls of the axial grooves and of the annular groove are arranged flush with one another.
 6. The bearing assembly according to claim 1, wherein the projecting parts of the bottom wall of the annular groove each include a first circumferential stretch of flat surface raised above the bottom wall of the annular groove and a pair of second circumferential stretches of flat surface which flank the first stretch and form two inclined planes which connect the first surface stretch to the bottom wall of the annular groove.
 7. The bearing assembly according to claim 1, wherein the cover has two pairs of teeth arranged so as to be symmetrically circumferentially spaced apart, staggered by 90°; the radially outer lateral surface of the housing element having two pairs of axial grooves arranged so as to be symmetrically circumferentially spaced apart, staggered by 90°; and the bottom wall of the annular groove having eight circumferential sectors having the same angular width, consisting of four depressions delimited by four curved surfaces arranged substantially flush with the bottom wall of the annular groove and of four projecting parts which radially protrude with respect to the bottom wall of the annular groove, arranged alternating with the depressions.
 8. The bearing assembly according to claim 1, wherein the cover is radially provided on the outside with a plurality of circumferential shallow recesses arranged so as to be circumferentially evenly spaced apart from one another, which are shaped so as to form respective gripping elements adapted to allow a user to manually rotate the cover with respect to the housing element.
 9. The bearing assembly according to claim 8, wherein the circumferential shallow recesses are obtained radially on the outside on the coupling portion and are made so as to make radially thinner the coupling portion at the shallow recesses themselves; the teeth of the cover being radially obtained on the inside of the coupling portion, at respective circumferential shallow recesses, the latter weakening the cover so as to make the coupling portion elastically deformable radially outwards at least at the teeth. 